Handbook of Railroad Construction; For the use of American engineers. / Containing the necessary rules, tables, and formulæ for the location, construction, equipment, and management of railroads, as built in the United States.

by George L. Vose

Fig. 103.

Represent C E by b, and E F by a, and the length of the semi-curve is

L = b[1 + ⅔(a
b)²].

Let the half span be five hundred feet, and the versed-sine or deflection eighty feet, the formula becomes

L = 500[1 + ⅔(80
500)²] = 500 × 1.0171 = 508.55 feet,

which is the half length of cables between towers.

Problem 2.

226. To find the length of the suspending rods. Calling E the horizontal distance between the vertical suspenders, we have the formula

X = Y²
b² × a,